1. Field of the Invention
The present invention relates to an internal combustion engine including a rotation detecting device for detecting the rotational speed of a gear in a transmission.
2. Description of Background Art
In connection with a transmission provided behind a crankcase, the transmission includes a shaft and a plurality of gears provided on the shaft. A rotation detecting device is known for detecting the rotational speed of the shaft in the transmission. The rotation detecting device includes a rotation sensor for detecting the rotational speed of a specific one of the plurality of gears in the transmission, the specific gear being movable in the axial direction of the shaft. See, for example, Japanese Patent Laid-Open No. 2000-87780.
In this conventional configuration, the rotation sensor is so as to face the axially movable gear in the transmission. Accordingly, to reliably detect the rotational speed of the axially movable gear regardless of the axial movement of this gear, the width of this gear in the axial direction must be increased or an expensive sensor having high sensitivity must be used as the rotation sensor.